Exercise Research Laboratory, School of Physical Education, Federal University of Rio Grande do Sul, Porto Alegre, Brazil.
Muscle Nerve. 2013 Oct;48(4):498-506. doi: 10.1002/mus.23785. Epub 2013 Jul 15.
Changes in muscle architecture induced by eccentric knee extensor training remain unclear, as well the adaptive responses of synergistic knee extensor muscles with different geometrical designs.
Ultrasonography images were taken from rectus femoris (RF) and vastus lateralis (VL) of 20 male volunteers before and after a non-training control period of 4 weeks, and additional evaluations were performed after 4, 8, and 12 weeks of isokinetic eccentric training.
RF and VL had significant changes in muscle architecture within the first 4 training weeks, and the adaptive response throughout the intervention was similar. Muscle thickness increased by around 7-10%, fascicle length increased 17-19%, and pennation angle was unchanged.
Increased muscle thickness due to eccentric training was related to increased fascicle length and not to pennation angle changes. Although RF and VL have a different fascicular geometry, they had similar morphological adaptations to eccentric training.
离心型膝关节伸展训练引起的肌肉结构变化尚不清楚，具有不同几何设计的协同性膝关节伸展肌的适应反应也不清楚。
20 名男性志愿者在非训练对照期 4 周前后接受股直肌（RF）和股外侧肌（VL）的超声图像检查，并在 4、8 和 12 周的等速离心训练后进行额外评估。
RF 和 VL 在最初的 4 周训练中肌肉结构发生了显著变化，整个干预过程中的适应反应相似。肌肉厚度增加了约 7-10%，肌束长度增加了 17-19%，而肌节角度不变。
由于离心训练导致的肌肉厚度增加与肌束长度的增加有关，而与肌节角度的变化无关。尽管 RF 和 VL 的肌束几何形状不同，但它们对离心训练有相似的形态适应。
